1. Field of the Invention
The invention relates to a method of establishing an electrical connection between metallizations of a semiconductor wafer and conductor tracks, which may be of metal, carried by a surface of a support, in which the thin support is provided with holes having a configuration corresponding to that of the metallizations on the wafer.
The method according to the invention can advantageously be used for the realization of a portable card having a semiconductor circuit, especially a credit card or an identity card, comprising flat conductor elements constituted by a conducting paste and connected to the terminals of the semiconductor circuit so that an electrical connection can be established with an external member and in which material the semiconductor circuit is directly included in the form of a semiconductor wafer, the terminals of which are constituted by metallizations.
The thin supports used in accordance with the invention are utilized in the electronic industry for providing a semiconductor wafer on a complex electronic circuit, while ensuring the mechanical strength as well as the electrical interconnection of the wafer.
2. Description of the Prior Art
The term "semiconductor circuit wafer" or in abbreviated form "semiconductor wafer" is to be understood herein as one of the elements obtained by cutting slices of semiconductor material, on which integrated circuits have been formed (these elements are generally designated in the professional language as "chips").
A solution for providing a wafer in a circuit consists in that a film is utilized which is retained in the finished product and which provides for the insulation with respect to the edges of the wafer due to its location between the conducting strip or track on one of the surfaces and the wafer on the other side. Such a solution is described in French Patent Application No. 2382 101 and is more particularly illustrated in its FIG. 3. In this case, use is made of a thin support (5) whose conductor tracks (4) are connected through metallized holes (6) to other conductor tracks on the other surface, which in turn is soldered to the metallizations (3) of the wafer (2).
However, this solution, which is excellent after all from a technical point of view, is expensive due to the use of two metallized surfaces, which requires two etching steps and the provision of metallized holes.